Graft anchor system and method

ABSTRACT

A graft anchor has first and second arms each having a leading end, a trailing end, an inner surface, and an outer bone contactable surface. The graft anchor also has a resilient bridge extending between the inner surface of the first arm and the inner surface of the second arm to space apart the first arm and the second arm. The resilient bridge defines a graft receiving pathway between the inner surfaces of the first and second arms. The resilient bridge also defines a deflection point about which a force acting upon the resilient bridge in a direction from the leading end to the trailing end causes the leading ends of the first and second arms to move toward one another and the trailing ends of the first and second arms to move away from one another.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/797,421, filed on Mar. 12, 2013, which claims priority to U.S.provisional application Ser. No. 61/619,705, filed on Apr. 3, 2012. Theentirety of each is expressly incorporated herein by reference.

BACKGROUND

Soft tissues such as tendons and ligaments are generally attached tobones by small collagenous fibers. These fibers are strong, but permittendons and ligaments to be flexible. When soft tissue is torn away fromthe bone, a surgeon is often required to reattach the soft tissue, or areplacement tissue graft to the bone with one of more surgical anchorsor other surgical fixation implants. Surgical fixation implants, such asscrews, surgical anchors, graft anchors, and surgical pins, may beimplanted into a patient's bone to reattach or fix soft tissue or toreinforce damaged bone. Fixation implants are implanted into bone usingextensive surgical procedures, and more recently, using arthroscopicsurgical techniques. A growing recent trend is to manufacture fixationimplants from bio-inert and bio-absorbable materials so that native bonetissue may gradually absorb the fixation implant and grow into the spaceoccupied by the fixation implant to replace the implant with native bonetissue.

A frequently performed procedure where fixation implants are routinelyused to attach a ligament graft to a bone is anterior cruciate ligament(ACL) reconstruction. This procedure generally involves removing thetorn or damaged ACL and forming tunnels in the distal femur and proximaltibia in close proximity to the original ACL attachments sites. Areplacement graft may be harvested from the patellar tendon (along witha portion of the patella and the tibia, i.e., a bone-to-bone graft),from the hamstring tendons of the patient, or from another donor. Thegraft may be pulled through or into the bone tunnels and fixed in thebone tunnels with a graft anchor. The graft may then be left to functionas a new ACL. The tibial portal is more commonly used for thisprocedure, but the antero-medial portal has seen some increased userecently.

Rigid fixation of the graft anchor is recognized as an important factorfor the long-term success of ACL reconstruction procedures. Rigidfixation is difficult to initially obtain, and even more difficult tomaintain throughout the life of the graft anchor.

One type of graft anchor commonly used to fix the ligament graft in ACLreconstructions is an interference screw, which biases a graft segment,against a wall of a bone tunnel (e.g., formed in the femur). However,use of interference screws may result in damage to the graft. Forexample, the threads of the interference screw, and the bone tunnel wallmay cut or abrade the graft as the interference screw is advanced intothe bone tunnel. Further, advancing the interference screw into the bonetunnel over the graft may twist the graft in a way that proper grafttension is lost or exceeded. In more severe cases, over-tightening ofthe interference screw may cause catastrophic failure of the bone tunnelknown as tunnel blowout.

Tunnel sealing is another important consideration in ACLreconstructions, as it is known that synovial fluid acting on theinterference screw may cause bone tunnel enlargement. For example,improper tunnel sealing may result in graft loosening, such as a bungeeeffect or windshield wiper effect.

Attempts have been made to overcome the above deficiencies in the priorart. However, such attempts involve multi-piece fixation implants whichrequire forming additional holes or tunnels into the bone (e.g.,transversely to the initial attachment tunnel), and thus result inincreased procedure duration and complexity, implant costs, surgeonerrors and failure rates, and prolong patient recovery time.

BRIEF DESCRIPTION OF THE DRAWINGS

To assist those of ordinary skill in the relevant art in making andusing the inventive concepts disclosed herein, reference is made to theappended drawings and schematics, which are not intended to be drawn toscale, and in which like reference numerals may refer to the same orsimilar elements for consistency. For purposes of clarity, not everycomponent may be labeled in every drawing. Certain features and certainviews of the figures may be shown exaggerated in scale or in schematicin the interest of clarity and conciseness. In the drawings:

FIG. 1 is a perspective view of an exemplary embodiment of a graftanchor according to the inventive concepts disclosed herein.

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1.

FIG. 3A is a bottom plan view of the graft anchor of FIG. 1.

FIG. 3B is a top plan view of the graft anchor of FIG. 1.

FIG. 4 is a side elevational view of the graft anchor of FIG. 1.

FIG. 5 is a perspective view of another exemplary embodiment of a graftanchor according to the inventive concepts disclosed herein.

FIG. 6A is a diagrammatic view of a femoral tunnel with a graft anchorand graft loop inserted therein.

FIG. 6B is a sectional view taken along line 6B-6B of FIG. 6A.

FIG. 7 is a diagrammatic view of an exemplary embodiment of an ACLreconstruction using a graft anchor system according to the inventiveconcepts disclosed herein.

FIG. 8 is a perspective view of an exemplary embodiment of a tibialgraft spacer according to the inventive concepts disclosed herein.

FIG. 9 is a perspective view of an exemplary embodiment of a tibialfixation button according to the inventive concepts disclosed herein.

FIG. 10A is a perspective view of an insertion tool constructedaccording to the inventive concepts disclosed herein.

FIG. 10B is an end view of the insertion tool of FIG. 10A.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Before explaining at least one embodiment of the inventive concepts indetail, it is to be understood that the inventive concepts disclosedherein are not limited in their application to the details ofconstruction, experiments, exemplary data, and the arrangement of thecomponents set forth in the following description or illustrated in thedrawings. The inventive concepts are capable of other embodiments orbeing practiced or carried out in various ways. Also, it is to beunderstood that the phraseology and terminology employed herein is forpurposes of description and should not be regarded as limiting.

In the following detailed description of embodiments of the inventiveconcepts, numerous specific details are set forth in order to provide amore thorough understanding of the inventive concepts. However, it willbe apparent to one of ordinary skill in the art that the inventiveconcepts within the disclosure may be practiced without these specificdetails. In other instances, certain well-known features may not bedescribed in detail to avoid unnecessarily complicating the instantdisclosure.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having,” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherently present therein.

Unless expressly stated to the contrary, “or” refers to an inclusive orand not to an exclusive or. For example, a condition A or B is satisfiedby anyone of the following: A is true (or present) and B is false (ornot present), A is false (or not present) and B is true (or present),and both A and B are true (or present).

The term “and combinations thereof” as used herein refers to allpermutations or combinations of the listed items preceding the term. Forexample, “A, B, C, and combinations thereof” is intended to include atleast one of: A, B, C, AB, AC, BC, or ABC, and if order is important ina particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB.Continuing with this example, expressly included are combinations thatcontain repeats of one or more item or term, such as BB, AAA, AAB, BBC,AAABCCCC, CBBAAA, CABABB, and so forth. A person of ordinary skill inthe art will understand that typically there is no limit on the numberof items or terms in any combination, unless otherwise apparent from thecontext.

In addition, use of the “a” or “an” are employed to describe elementsand components of the embodiments herein. This is done merely forconvenience and to give a general sense of the inventive concepts. Thisdescription should be read to include one or at least one and thesingular also includes the plural unless it is obvious that it is meantotherwise.

The use of the terms “at least one” and “one or more” will be understoodto include one as well as any quantity more than one, including but notlimited to each of, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 100, and allintegers and fractions, if applicable, therebetween. The terms “at leastone” and “one or more” may extend up to 100 or 1000 or more, dependingon the term to which it is attached; in addition, the quantities of100/1000 are not to be considered limiting, as higher limits may alsoproduce satisfactory results.

Further, as used herein any reference to “one embodiment” or “anembodiment” means that a particular element, feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. The appearances of the phrase “in oneembodiment” in various places in the specification are not necessarilyall referring to the same embodiment.

As used herein qualifiers such as “about,” “approximately,” and“substantially” are intended to signify that the item being qualified isnot limited to the exact value specified, but includes some slightvariations or deviations therefrom, caused by measuring error,manufacturing tolerances, stress exerted on various parts, wear andtear, and combinations thereof, for example.

Further, as used herein, the term “patient” is meant to include allorganisms, whether alive or dead, including all species of animals. Forexample, a graft anchor system according to the inventive conceptsdisclosed herein may be used to treat a detachment, tear, or other softtissue injury, in a human being, a horse, a cow, a sheep, a cat, a dog,and other organisms. As another example, a graft anchor according to theinstant disclosure may be used in a non-living human cadaver or otherappropriate natural or artificial model to train medical or veterinarypersonnel in surgical techniques. As yet another example, a graft anchorsystem according to the inventive concepts disclosed herein may be usedto implant other medical devices such as replacement joints, pacemakers,and the like, into an organism, by anchoring or fixing such medicaldevices to a bone. As yet another example, a method according to theinventive concepts disclosed herein may be used to repair rotator cuffinstabilities and tears in shoulder surgery, or to repair various knee,elbow, hip, wrist, ankle, or other soft tissue tears or detachments andjoint injuries.

Also, as used herein the terms graft, grafts, graft loop, and anyvariations thereof, are intended to include natural materials, such astendons, ligaments, connective tissue, collagen fibers, and combinationsthereof, and encompassing autografts, allografts, and xenografts (orheterografts). Further, said terms include synthetic substitutes forligaments and tendons, and combinations of natural materials andsynthetic substitutes, for example. Synthetic substitutes may includemetallic materials, ceramics, polymeric materials, fibrous braidimplants, implants comprised of textiles or fabrics, and combinationsthereof, for example. Finally, said terms include a combination ofnatural materials and synthetic substitutes, and comprise a graft, agraft loop, and a graft bundle, and combinations thereof, for example.

The inventive concepts disclosed herein will be described in connectionwith ACL reconstruction. It is to be understood that, while thisdescription relates to the attachment of a ligament graft to a femur anda tibia located within a knee of a patient, the inventive conceptsdisclosed herein are not limited to ACL reconstruction procedures. Agraft anchor, a graft anchor system, and a method according to theinventive concepts disclosed herein may be used to fix or secure aligament, a tendon, or other soft tissue, to any bone, whether suchligament, tendon, or soft tissue is secured with the use of sutures ornot.

The inventive concepts disclosed herein are generally directed to agraft anchor system for anchoring a graft into a bone tunnel and to amethod of using same. The graft anchor system includes a graft anchorwhich may be generally cylindrical and comprises a pair of armssupported in a spaced apart relationship by a resilient bridge. The armshave a trailing end, a leading end, and an outer side configured toconform to the contour of a bone tunnel. The bridge has inwardly curvedsides and an inwardly curved distal side cooperating with the arms todefine a graft receiving pathway. The graft receiving pathway isconfigured to allow a portion of the graft to contact the bone tunnel. Agraft may be inserted into the graft receiving pathway such that thegraft loops around the graft anchor. The graft anchor may then theninserted into a bone tunnel and retained inside the bone tunnel via acombination of scissor-like pivoting motion of the arms about the bridgeand bone engaging and/or retention features formed on the outer sides ofthe arms, as will be described below.

Referring now to the drawings, and in particular to FIGS. 1-4, a graftanchor 100 according to the inventive concepts disclosed herein isshown. The graft anchor 100 generally includes a first arm 102 a and asecond arm 102 b supported in a spaced-apart relationship by a bridge104.

In the exemplary embodiment, the first arm 102 a and the second arm 102b are shown as substantially identical in structure and function. It isto be understood, however, that while the first arm 102 a and second arm102 b are shown to allow for a symmetrical engagement of the graftanchor 100 into a bone tunnel, in some exemplary embodiments, the firstarm 102 a and the second arm 102 b may be implemented differently fromone another, such as by having different sizes, different surfacefeatures, or by being made of different materials, for example. Further,in some exemplary embodiments, the graft anchor 100 may be implementedwith more than two arms.

The first arm 102 a has a trailing end 106 a, a leading end 108 a, aninner side or surface 110 a, an outer side 112 a, and a length 114 aextending from the trailing end 106 a to the leading end 108 a. Theleading end 108 a of the first arm 102 a may be tapered to allow foreasier insertion of the graft anchor 100 into a bone tunnel, forexample.

The outer side 112 a is configured to substantially conform to thecontour of a bone tunnel along the length 114 a of the first arm 102 a.The outer side 112 a is shown as having a substantially cylindricalshape configured to conform to the contour of a substantiallycylindrical bone tunnel as will be described in detail below. It is tobe understood that the outer side 112 a may have any other suitable formconfigured to conform to the contour of a bone tunnel, such as oval,elliptical, irregular, and combinations thereof, for example.

The outer side 112 a may further include one or more serrations 116 aformed thereon and configured for gripping engagement with a femoralbone tunnel. It is to be understood that, while the outer side 112 a isshown as having serrations 116 a formed thereon, in some exemplaryembodiments only a part of the outer side 112 a may have serrations 116a, and a part of the outer side 112 a may lack serrations 116 a.Further, in some exemplary embodiments other retention structures, suchas grooves, threads, spikes, bumps, striations, barbs, pins, knurls, andcombinations thereof may be implemented, instead of, or in combinationwith serrations 116 a.

The outer side 112 a may be further provided with one or morebone-engaging protrusions 120 a extending therefrom and configured toengage a portion of the femoral bone tunnel. In an exemplary embodiment,the bone-engaging protrusion 120 a extends at an angle α (FIG. 2)relative to the outer side 112 a in a direction from the leading end 108a to the trailing end 106 a. The angle α may vary from approximately 0°to approximately 90°, for example. In an exemplary embodiment, the angleα may be approximately 30°. The bone-engaging protrusion 120 a may besized such that the bone-engaging protrusion 120 a does not extend pastthe trailing end 106 a of the first arm 102 a. An end of thebone-engaging protrusion 120 a may finish a predetermined distancebefore the trailing end 106 a. The predetermined distance may be chosenso that the bone-engaging protrusion 120 a passes through the cancellousbone and contacts the cortical bone surrounding an entrance into thefemoral bone tunnel to achieve so called “aperture fixation” when thegraft anchor 100 is inserted into the femoral bone tunnel. Thepredetermined distance may be in a range of 2 mm to 4 mm and could bechosen according to the type of person in which the graft anchor is tobe implanted. For example, in an averaged-sized Caucasian male, thedistance may be about 4 mm and, in an average-sized Asian female, thedistance may be about 2 mm.

In one version, the bone-engaging protrusion 120 a may be configured inthe operating room by a surgeon to have an appropriate predetermineddistance. In another version, a range of graft anchors may be providedhaving, for example, a predetermined distance of 2 mm, 3 mm, and 4 mm,so that a surgeon may select a graft anchor according to a determinationof the size of the cortical bone of the patient. Also, the bone-engagingprotrusion 120 a may be constructed of a resilient material such thatthe bone-engaging protrusion 120 a is pressed substantially flat againstthe outer side 112 a as the graft anchor 100 is inserted into thefemoral bone tunnel, but extend outwards when tension is applied to thegraft anchor 100 to prevent backing-out of the graft anchor 100, forexample.

One or more openings 124 a may be formed in the first arm 102 a suchthat the openings 124 a extend through the first arm 102 a from theinner side 110 a to the outer side 112 a. The openings 124 a may beconfigured to receive one or more sutures (not shown) or suture loops(not shown) therein. It is to be understood that in some exemplaryembodiments, the openings 124 a may be implemented as notches, hooks, orslits, for example. The openings 124 a may be formed into the first arm102 a in any suitable manner, and may function to allow one or moresutures or suture loops to be inserted therein, so that the graft anchor100 may be pulled or guided by the sutures into the femoral bone tunnelas will be described below.

The openings 124 a may also serve to facilitate bone tissue integrationinto the graft anchor 100. It is to be understood that while threeopenings 124 a are shown in the first arm 102 a, some embodiments mayinclude only one opening, two openings, or more than two openings, forexample. Further, while the one or more openings 124 a are shown asbeing aligned, it is to be understood that in some embodiments theopenings 124 a may be staggered, or offset.

The second arm 102 b may be implemented and may function substantiallysimilarly to the first arm 102 a, and thus includes a trailing end 106b, a leading end 108 b, an inner side or surface 110 b, an outer side112 b, and a length 114 b extending from the trailing end 106 b to theleading end 108 b. It is to be understood that in some exemplaryembodiments, the second arm 102 b may be implemented differently fromthe first arm 102 a, such as for example, by having a different length,different bone-retention features, different arrangement, and number ofopenings 124 b, and combinations thereof.

The bridge 104 has an inwardly curved first side or surface 130 a, aninwardly curved second side or surface 130 b, and an inwardly curveddistal side 132. The bridge 104 extends between the inner side 110 a ofthe first arm 102 a and the inner side 110 b of the second arm 102 b soas to support the first arm 102 a and the second arm 102 b in a spacedapart relationship with the outer side 112 a of the first arm 102 a andthe outer side 112 b of the second arm 102 b in an opposing relationshiprelative to one another. The inwardly curved first side 130 a, theinwardly curved second side 130 b, and the inwardly curved distal side132 cooperate with the first arm 102 a and the second arm 102 b todefine a smooth graft receiving surface and a graft receiving pathway134. In one version, the graft receiving pathway 134 has a predeterminedsealing dimension selected according to the size of the graft. The graftreceiving pathway 134 has a first channel 135 a and a second channel 135b. The first channel 135 a is defined by the inner surfaces 110 a and110 b of the first and second arms 102 a and 102 b, and the firstsurface 130 a of the resilient bridge 134. The second channel 135 b isdefined by the inner surfaces 110 a and 110 b of the first and secondarms 102 a and 102 b, and the second surface 130 b of the resilientbridge 134. The sealing dimensions of the first and second channels 135a and 135 b are chosen to receive a graft therein in such a way that thegraft and the graft anchor 100 cooperate to form a seal in the entranceof a bone tunnel in a manner to be discussed below.

The distal side 132 of the bridge 104 defines a bearing surface betweenthe first channel 135 a and the second channel 135 b. The bridge 104 isconstructed of a resilient and flexible material, such that the bridge104 may deform, flex, or compress, under pressure (represented by arrow105 in FIG. 2) to allow the leading end 108 a of the first arm 102 a andthe leading end 108 b of the second arm 102 b to move toward one another(represented by arrows in FIG. 2), and to allow the trailing end 106 aof the first arm 102 a, and the trailing end 106 b of the second arm 102b to move away from one another (represented by arrows in FIG. 2) when atensile force is applied to a graft positioned in the graft receivingpathway 134, to enhance the fixation of the graft anchor 100 into thebone tunnel, as will be described below.

The bridge 104 may further include one or more synovial fluid drain 136formed therein such that the inwardly curved first side 130 a is influid communication with the inwardly curved second side 130 b to allowany synovial fluid to flow from the inwardly curved first side 130 a andthe inwardly curved second side 130 b. It is to be understood, however,that in some embodiments the synovial fluid drain 136 may be omitted,for example, or two, three, or more synovial fluid drains 136 may beimplemented. Further, while the synovial fluid drain 136 is shown asbeing substantially cylindrical in shape, the synovial fluid drain 136may be implemented as oval, square, polygonal, star-shaped, andcombinations thereof, or may have any other suitable shape, for example.

The graft anchor 100 may be made of any suitable material orcombinations of materials including resorbable and non-resorbablepolymers, such as polyethylene, polypropylene, ultra high molecularweight polyethylene, poly-ether-ether-ketone (PEEK),poly-ether-ketone-ketone (PEKK), resorbable polymers, such aspoly-lactic acid (PLA), poly-L-lactide (PLLA), poly-L/D-lactide (PLDLA),poly-lactic-co-glycolic acid (PLGA), poly-glycolide or poly-glycolicacid (PGA), poly-capro-lactone (PCL), or soft metals, such as nitinol.The graft anchor 100 may be uncoated, coated, or impregnated withvarious substances, such as for example antibiotics, titanium, titaniummodified with an anodic plasma-chemical (APC) process, and combinationsthereof, for example. The graft anchor 100 may be constructed using anydesired methods, such as injection molding, casting, machining, molding,thermoplastic setting, 3D printing, and combinations thereof, forexample.

Referring now to FIG. 5 a second embodiment of a graft anchor 100′according to the inventive concepts disclosed herein is shown. The graftanchor 100′ has all features in common with the graft anchor 100, withthe exception that the first arm 102 a′ is shorter in length than thesecond arm 102 b′. For example, the first arm 102 a′ is between about 1mm and about 15 mm shorter than the second arm 102 b′. Other differencesin arm length are of course possible, as the skilled person wouldappreciate. The first arm 102 a′, which is shortened, may facilitateeasier catching of a graft. During surgery, a suture will be positionedin the bone tunnel in the femur for guiding the graft anchor 100′ intothe bone tunnel, for example. The suture may then be positioned to passthrough a loop formed in the graft. This suture is inserted through anopening 124′ formed in the graft anchor 100′. The graft anchor 100′ isthen guided into position in the bone tunnel by sliding it along thesuture. Along its route to the bone tunnel, the graft anchor 100′ maycome into contact with the graft. In particular, an internal surface ofthe arm 102 b′ may contact the graft first, which guides the graft intothe space between the first arm 102 a′ and the second arm 102 b′ (or thegraft receiving pathway 134′), where the graft is anchored afterimplantation.

Referring now to FIGS. 6A-6B, the graft anchor 100 is shown positionedinside a femoral bone tunnel 118 with a graft 140 positioned in thegraft receiving pathway 134 such that at least a portion of the graft140 is in contact with the bridge 104 and with the femoral bone tunnel118, for example. As shown in FIG. 6B, the graft anchor 100 cooperateswith the graft 140 to substantially seal the femoral bone tunnel 118such that at least a portion of the graft 140 is maintained in contactwith the femoral bone tunnel 118 to facilitate attachment of the graft140 to the bone tissue inside the femoral bone tunnel 118.

The graft anchor 100 is designed to be atraumatic, i.e., to minimize thedamage and pressure exerted by the graft anchor 100 to the femoral bonetunnel 118 and to the graft 140. For example, the graft anchor 100 isdesigned to exert symmetrical pressure on the femoral bone tunnel 118,and such pressure is spread out over the outer side 112 a and the outerside 112 b to minimize the chance of femoral bone tunnel 118 enlargementor blowout. Further, the graft receiving pathway 134 is designed toprotect the graft 140 from damage during the insertion of the graftanchor 100 into the femoral bone tunnel 118, while at the same timemaximizing the contact surface between the femoral bone tunnel 118 andthe graft 140. Further, the openings 124 a and 124 b may serve toaccelerate bone tissue integration of the graft anchor 100 by providingspaces to encourage bone ingrowth into the graft anchor 100. Evenfurther, the bone-engaging protrusions 120 a and 120 b are sized andpositioned such that the bone-engaging protrusions 120 a and 120 bextend into the cancellous portion of the bone and beneath the corticalportion of the bone to preserve the integrity and mechanical strength ofthe cortical portion of the bone surrounding the femoral bone tunnel 118and to further minimize the risks for tunnel enlargement and blowouts,for example.

Referring now to FIG. 7 shown therein is a graft anchor system 150according to an exemplary embodiment of the inventive concepts disclosedherein. The graft anchor system 150 comprises a graft anchor 100, atibial graft spacer 152, and a tibial fixation implant 154. The graftanchor 100 is inserted into a femoral bone tunnel 118, and secures agraft 140 inside the femoral bone tunnel 118. The tibial graft spacer152 is inserted into a tibial bone tunnel 160 and guides the graft 140through the tibial bone tunnel 160. The tibial fixation implant 154 isinserted into an end of the tibial bone tunnel 160 and anchors one ormore sutures 158 attached to the graft 140 such that appropriate tensionis maintained on the graft 140.

Referring now to FIG. 8, the tibial graft spacer 152 comprises a firstend 162, a second end 164, and an outer side 166. The outer side 166extends a length L from the first end 162 to the second end 164 and isconfigured to substantially conform to the contour of the tibial bonetunnel 160, and is provided with serrations 168 for engaging the tibialbone tunnel 160 so as to retain the tibial graft spacer 152 inside thetibial bone tunnel 160. The outer side 166 further defines one or moreinwardly curved grooves 170 extending from the first end 162 to thesecond end 164 thereof. The grooves 170 are configured to receive andretain at least a portion of the graft 140 therein.

The tibial graft spacer 152 may include one or more synovial fluiddrains (not shown) to allow fluid communication between the grooves 170.The tibial graft spacer 152 is configured to guide the graft 140 in thetibial bone tunnel 160 such that at least a portion of the graft 140 ismaintained in contact with the tibial bone tunnel 160 when the tibialgraft spacer 152 and graft 140 are inserted therein and thereby allowthe graft 140 to attach to the bone tissue inside the tibial bone tunnel160.

It is to be understood that in some exemplary embodiments of theinventive concepts disclosed herein, two or more than two tibial graftspacers 152 may be implemented depending on the length of the tibialbone tunnel 160 and the length of the tibial graft spacers 152. Further,in some exemplary embodiments of the inventive concepts disclosedherein, the tibial graft spacer 152 may be omitted. The tibial graftspacer 152 may be made of similar materials and using similar techniquesas the graft anchor 100.

Referring now to FIG. 9, the tibial fixation implant 154 comprises afirst end 172, a second end 174, an outer side 176 configured to conformto the contour of the tibial bone tunnel 160, and a flange 178 having adiameter larger than the diameter of the tibial bone tunnel 160. Theouter side 176 is configured to be inserted into the tibial bone tunnel160 and is provided with serrations 180 configured to engage the tibialbone tunnel 160 and retain the tibial fixation implant 154 therein. Theouter side 176 further has one or more suture notches 182 formed thereinand configured to allow for one or more sutures 158 (FIG. 7) attached tothe graft 140 to extend at least partially therethrough so that thesutures 158 may be used to anchor the graft 140 to the tibial fixationimplant 154 and impart an appropriate tension thereto. The sutures 158may be anchored by the tibial fixation implant 154 by passing thesutures 158 through the suture notches 182 and tying off the sutures 158at the appropriate tension. The flange 178 may rest against the surfaceof the tibia when the tibial fixation implant 154 is inserted into thetibial bone tunnel 160 and may function to prevent the tibial fixationimplant 154 from migrating into the tibial bone tunnel 160 when tensionis applied to the tibial fixation implant 154 by the sutures 158. Thetibial fixation implant 154 may be constructed and implemented similarlyto the graft anchor 100, and may be constructed of PEEK, for example.

Referring now to FIGS. 10A-10B, shown is an exemplary embodiment of aninsertion tool 184 which may be employed to insert the graft anchor 100and the tibial graft spacer 152 into a respective bone tunnel accordingto the inventive concepts disclosed herein. The insertion tool 184 maycomprise a handle 186 and a shaft 188 extending longitudinally from thehandle 186. The insertion tool 184 is configured to allow a user, suchas a surgeon or a surgical robot, for example, to push, press, orotherwise insert the graft anchor 100 into a bone tunnel, as will bedescribed below. The insertion tool 184 may also be used in conjunctionwith a navigation system.

The handle 186 may be implemented as a conventional surgical instrumenthandle and may comprise grip-enhancing features, such as rubberizedportions, grooves, striations, bumps, knurls, and combinations thereof,for example. The handle 186 may comprise a suture collar 190 configuredto receive and retain one or more sutures therein such that the graft140 may be manipulated via one or more sutures 158 (FIG. 7) attached tothe graft 140 during the insertion of the graft anchor 100 and thetibial graft spacer 152 into the respective bone tunnels 118 and 160.

The shaft 188 may comprise a tip 192 and may have one or more inwardlycurved graft grooves 194 extending at least partially along the lengthof the shaft 188 and configured to receive at least a portion of thegraft 140 therein during the use of the insertion tool 184. The shaft188 is configured such that the tip 192 corresponds to and contacts thegraft anchor 100, but does not contact the graft 140 to avoid damage tothe graft 140 by the tip 192. A suture attached to the graft 140 may beused to guide the graft 140 away from the tip 192 and secure the graft140 by securing the one or more sutures in the suture collar 190, forexample. Similarly, the tip 192 is configured to contact the first end162 and/or the second end 164 of the tibial graft spacer 152 withoutdamaging the graft 140 to insert the tibial graft spacer 152 inside thetibial bone tunnel 160 and/or adjust the position of the tibial graftspacer 152 inside the tibial bone tunnel 160, for example.

In some exemplary embodiments, the insertion tool 184 may be cannulatedsuch that a guide wire (not shown) may be used to guide the insertiontool 184 into the femoral bone tunnel 118 or the tibial bone tunnel 160,while in other exemplary embodiments the insertion tool 184 may benon-cannulated.

It is to be understood that any suitable surgical tool may be used toinsert the graft anchor 100, the tibial graft spacer 152, and the tibialfixation implant 154 into a bone tunnel. Further, a first surgical toolmaybe used to insert the graft anchor 100 in the femoral bone tunnel118, a second surgical tool may be used to insert the tibial graftspacer 152 into the tibial bone tunnel 160, and a third surgical toolmay be used to insert the tibial fixation implant 154 into the tibialbone tunnel 160, for example.

In use, a method for ACL replacement using the graft anchor system 150according to the inventive concepts disclosed herein comprises capturinga graft 140 with a graft anchor 100. Capturing the graft 140 maycomprise inserting a portion of the graft 140 into the graft receivingpathway 134 of the graft anchor 100. In one version, the graft receivingpathway 134 is sized such that the graft 140 and the graft anchor 100cooperate to form a seal in the bone tunnel 118 (FIG. 6B). Additionally,one or more sutures may be passed through one or more of the openings124 a and 124 b formed in the first arm 102 a and the second arm 102 brespectively, for example. Such sutures may be inserted prior to,simultaneously with, or after, capturing the graft 140 into the graftreceiving pathway 134, and may function to secure the graft 140 in thegraft receiving pathway 134. Such sutures may further be used to guidethe graft anchor 100 toward, or into, the femoral bone tunnel 118, forexample.

The insertion tool 184 may be used to insert the graft anchor 100 intothe femoral bone tunnel 118 such that the graft anchor 100 sitssubstantially level with the surface of the femur, extends slightlyabove the surface of the femur, or sits slightly below the surface ofthe femur, for example. The graft 140 desirably extends through thegraft receiving pathway 134 and past the trailing end 106 a of the firstarm 102 a and the trailing end 106 b of the second arm 102 b.

The tibial graft spacer 152 may be inserted in the tibial bone tunnel160 via the insertion tool 184, and the graft 140 may be guided into thetibial bone tunnel 160 and at least partially into the one or moregrooves 170, such that the graft 140 extends past the second end 164 ofthe tibial graft spacer 152, for example. In some exemplary embodiments,the graft 140 may not extend past the second end 164, and one or moresutures 158 (FIG. 7) attached to the graft 140 may extend past thesecond end 164 instead, as will be understood by persons of ordinaryskill in the art. In some exemplary embodiments, the graft 140 may besecured into the one or more grooves 170 prior to inserting the tibialgraft spacer 152 into the tibial bone tunnel 160, and the graft 140 andthe tibial graft spacer 152 may be inserted into the tibial bone tunnel160 simultaneously. In other embodiments, a portion of the graft 140 maybe inserted into the tibial bone tunnel 160 prior to inserting thetibial graft spacer 152 into the tibial bone tunnel 160. Further, insome exemplary embodiments, the tibial graft spacer 152 may be omitted.It is to be understood that the tibial graft spacer 152 may be insertedinto the tibial tunnel 160 from either side of the tibial tunnel 160,for example.

The one or more sutures 158 attached to the graft 140 are passed throughthe tibial bone tunnel 160 such that the sutures 158 extend past an endof the tibial bone tunnel 160, for example. The sutures 158 may bepassed through the one or more suture notches 182 such that the sutures158 extend past the second end 174 of the tibial fixation implant 154,as shown in FIG. 7.

The first end 172 of the tibial fixation implant 154 is inserted intothe tibial bone tunnel 160, such that the outer side 176 engages thetibial bone tunnel 160, and the flange 178 sits against, adjacent to, orslightly above the surface of the tibia. One or more washers (notshown), seals (not shown), or other implants (not shown) may bepositioned between the flange 178 and the tibia, as will be understoodby persons of ordinary skill in the art.

The sutures 158 may be tensioned at the appropriate tension, and one ormore knots may be tied to secure the sutures 158 to the tibial fixationimplant 154 at any desired tension. Any excess portions of the one ormore sutures 158 may be trimmed and removed as needed or desired.

During body movements, as movement-related tension is applied to thegraft 140, such tension is transferred as force to the bridge 104. Thebridge 104 is at least partially compressed or deformed by the appliedtension or force, which causes the first arm 102 a and the second arm102 b to pivot about the bridge 104 relative to one another. Due to thedirection of the tension or force being from the leading ends 108 a and108 b towards the trailing ends 106 a and 106 b, the leading ends 108 aand 108 b will tend to move towards one another (FIG. 2) and thetrailing ends 106 a and 106 b will tend to move away from one another(FIG. 2), for example. This scissor-like pivoting of the first arm 102 aand the second arm 102 b about the bridge 104 may cause the one or morebone-engaging protrusions 120 a and 120 b to transfer some of the forceto the femoral bone tunnel 118 and substantially prevent backing out ofthe graft anchor 100. Further, the outer side 112 a and the outer side112 b transfer a portion of the force to the femoral bone tunnel 118 bydistributing such force over the outer side 112 a and the outer side 112b, respectively. Such symmetrical force distribution over several areasinside the femoral bone tunnel 118 may allow for securely retaining thegraft anchor 100 inside the femoral bone tunnel 118 without causing anyunnecessary trauma or damage to the bone by concentrating the force ontoa single point or narrow area of the femoral bone tunnel 118, forexample.

It is to be understood that a method according to the inventive conceptsdisclosed herein may utilize the tibial portal, the antero-medialportal, the lateral portal, or any other suitable portal or incision,for example.

As will be appreciated by persons of ordinary skill in the art, thegraft anchor 100′ may function substantially similarly to the graftanchor 100 as described above. Further, the graft anchor 100′ may beimplemented with a graft fixation system substantially similar to thegraft anchor system 150 as described above.

While the inventive concepts disclosed herein have been described inconnection with the exemplary embodiments of the various figures, theyare not limited thereto and it is to be understood that other similarembodiments may be used or modifications and additions may be made tothe described embodiments for performing the same function of theinventive concepts disclosed herein without deviating therefrom.Therefore, the inventive concepts disclosed herein should not be limitedto any single embodiment, but rather should be construed in breadth andscope in accordance with the appended claims. Also, the appended claimsshould be construed to include other variants and embodiments of theinventive concepts disclosed herein, which may be made by those skilledin the art without departing from the broad scope thereof.

What is claimed is:
 1. A graft anchor, comprising: a first arm having aleading end, a trailing end, an inner surface, and an outer bonecontactable surface; a second arm having a leading end, a trailing end,an inner surface, and an outer bone contactable surface; a bridgeextending between the inner surface of the first arm and the innersurface of the second arm to space apart the first arm and the secondarm, the bridge defining a graft receiving pathway between the innersurfaces of the first and second arms, the graft receiving pathwayhaving a predetermined sealing dimension selected according to the sizeof the graft, wherein the sealing dimensions of the first and secondchannels are chosen to receive a graft therein in a way that the graftand the graft anchor cooperate to form a seal in the entrance of a bonetunnel.
 2. The graft anchor of claim 1, wherein the graft receivingpathway has a first channel defined by the inner surfaces of the firstand second arms and a first surface of the bridge and a second channeldefined by the inner surfaces of the first and second arms and a secondsurface of the bridge, the second surface located on a side of thebridge opposite to the side on which the first surface is located. 3.The graft anchor of claim 2, wherein each of the first arm and thesecond arm has at least one bone engaging protrusion extending from theouter surface thereof at a location lateral to the bridge.
 4. The graftanchor implant of claim 3, wherein the bone engaging protrusions extendfrom the outer surface of the first arm and the second arm in adirection away from the trailing end of the first and second arms. 5.The graft anchor of claim 3, wherein, measured in a direction from theleading end to the trailing end of the first and second arms, the boneengaging protrusion ends a predetermined distance before the trailingends.
 6. The graft anchor of claim 2, wherein the bridge is located in aregion adjacent the trailing ends of the first and second arms.
 7. Thegraft anchor of claim 1, wherein the first arm has at least one holeextending through the first arm from the inner surface to the outersurface between an upper side of the bridge and the leading end of thefirst arm.
 8. The graft anchor of claim 7, wherein the second arm has atleast one hole extending through the second arm from the inner surfaceto the outer surface between the upper side of the bridge and theleading end of the second arm.
 9. The graft anchor of claim 1, whereinthe outer surfaces of each of the first and second arms are configuredto substantially conform to the contour of a bone tunnel and have aplurality of serrations formed thereon adapted for gripping engagementwith the bone tunnel.
 10. A graft anchor system, comprising: a graft;and a graft anchor comprising: a first arm having a leading end, atrailing end, an inner surface, and an outer bone contactable surface; asecond arm having a leading end, a trailing end, an inner surface, andan outer bone contactable surface; and a bridge extending between theinner surface of the first arm and the inner surface of the second armto space apart the first arm and the second arm, the bridge defining agraft receiving pathway between the inner surfaces of the first andsecond arms, the graft receiving pathway having a predetermined sealingdimension selected according to the size of the graft, wherein the graftis positioned in the graft receiving pathway of the anchor graft in away that the graft and the graft anchor cooperate to seal a bone tunnelwhen the graft and the graft anchor are positioned in the bone tunnel.11. The graft anchor system of claim 10, further comprising a tibialgraft spacer having a first end, a second end, and an outer sideconfigured to substantially conform to the contour of a tibial bonetunnel along a length of the outer surface from the first end to thesecond end, the outer surface having a plurality of serrations formedthereon adapted for gripping engagement with the tibial bone tunnel, theouter side defining at least one groove extending from the first end tothe second end and curved inwardly to receive at least a portion of thegraft therein; and a tibial fixation implant having a first end, asecond end, and an outer side configured to substantially conform to thecontour of the tibial bone tunnel, and a flange having a first diameterlarger than a diameter of the tibial bone tunnel, the outer side havingat least one notch formed therein for receiving a suture attached to thegraft.
 12. The graft anchor system of claim 10, wherein the graftreceiving pathway has a first channel defined by the inner surfaces ofthe first and second arms and a first surface of the bridge and a secondchannel defined by the inner surfaces of the first and second arms and asecond surface of the bridge, the second surface located on a side ofthe bridge opposite to the side on which the first surface is located.13. The graft anchor system of claim 10, wherein the bridge is resilientand defines a deflection point about which a force acting upon theresilient bridge in a direction from the leading end to the trailing endcauses the leading ends of the first and second arms to move toward oneanother and the trailing ends of the first and second arms to move awayfrom each other.
 14. The graft anchor of claim 10, wherein each of thefirst arm and the second arm has at least one bone engaging protrusionextending from the outer surface thereof at a location lateral to thebridge.
 15. The graft anchor implant of claim 14, wherein the boneengaging protrusions extend from the outer surface of the first arm andthe second arm in a direction away from the trailing end of the firstand second arms.
 16. The graft anchor of claim 15, wherein, measured ina direction from the leading end to the trailing end of the first andsecond arms, the bone engaging protrusion ends a predetermined distancebefore the trailing ends.
 17. The graft anchor of claim 10, wherein theouter surfaces of each of the first and second arms are configured tosubstantially conform to the contour of a bone tunnel and have aplurality of serrations formed thereon adapted for gripping engagementwith the bone tunnel.
 18. A method of anchoring a graft, comprising:forming a tunnel in a bone; selecting a graft anchor comprising: a firstarm having a leading end, a trailing end, an inner surface, and an outerbone contact surface; a second arm having a leading end, a trailing end,an inner surface, and an outer bone contact surface; and a bridgeextending between the inner surface of the first arm and the innersurface of the second arm to space apart the first arm and the secondarm, the bridge defining a graft receiving pathway between the innersurfaces of the first and second arms, the graft receiving pathwayhaving a predetermined sealing dimension selected according to the sizeof the graft; positioning the graft in the graft receiving pathway ofthe graft anchor; and fixing the graft anchor in the tunnel of the bonein a way that the graft and the graft anchor cooperate to seal thetunnel.
 19. The method of claim 18, wherein at least a portion of thegraft is maintained in contact with the bone when the graft anchor isfixed in the tunnel.
 20. The method of claim 18, wherein the bone is afemur, and wherein the method further comprises: forming a tibial bonetunnel; selecting a tibial graft spacer having a first end, a secondend, and an outer side configured to substantially conform to thecontour of a tibial bone tunnel along a length of the outer surface fromthe first end to the second end, the outer side defining at least onegroove extending from the first end to the second end and curvedinwardly to receive at least a portion of the graft therein; positioningthe graft in the groove of the tibial graft spacer; positioning thetibial graft spacer in the tibial bone tunnel with the graft extendingthrough the groove; selecting a tibial fixation implant having a firstend, a second end, and an outer side configured to substantially conformto the contour of the tibial bone tunnel, and a flange having a firstdiameter larger than a diameter of the tibial bone tunnel; inserting thetibial fixation implant into an end of the tibial bone tunnel; andsecuring the graft to the tibial fixation implant in a way thatappropriate tension is maintained on the graft.